Not able to join league

My friend is currently unable to join my league after leaving his previous league, and the issue has been ongoing for at least three weeks. His username is KingHenry, and his previous league was called Genesis. Despite multiple attempts and some basic troubleshooting like restarting the app and checking league settings, he still cannot join. It seems his account might be stuck or facing a restriction. We would appreciate it if you could look into this issue and help resolve it so he can successfully join my league without further delays. Thank you for your assistance.